The background of the invention will be discussed in two parts:
1. Field of the Invention
This invention relates to sound reproduction devices, and more particularly to sound reproduction devices with magnetic governors for use in toys.
2. Description of the Prior Art
Mechanically actuated sound reproduction units have been used in toys for enabling a child to hear a saying, or the like from the toy, in response to actuation of a pull string, or operation of a lever, or the like. Such sound reproduction units are compact and include a record disc, cylinder or tape, with a number of different phrases, or sayings, which may be randomly, sequentially, or selectively reproduced.
A salient characteristic for such sound reproduction units is a governor, usually mechanical in form, which regulates the speed of the record or tape, to provide a reasonably faithful reproduction of the recorded sound. In a typical prior art unit, the governor will consist of pivoted weights, having friction pads such as brake shoes, operating against the interior of a drum-like housing, with the weights being spring-biased toward the center of the device. A conventional design of such a governor is shown and described in U.S. Pat. No. 2,847,095, issued Aug. 12, 1958 to Sohlberg, et al.
One such prior art sound reproduction unit with a mechanical governor is shown and described in U.S. Pat. No. 3,370,855, entitled "Audio Device", issued to Lindsay on Feb. 27, 1968, the governor using pivotable weights with brake pads operating against the interior of a cylindrical housing to regulate the speed of the turntable.
U.S. Pat. No. 3,468,546 directed to "Sequential Play Phonograph", issued to Duncan et al on Sept. 23, 1969, illustrates another sound reproduction unit, mechanically activated by a pull string, in which the governor is of the type having a rotor with spring loaded outwardly displaceable arms having friction pads on the outer surfaces thereof for frictionally engaging the interior of a drum like housing.
U.S. Pat. No. 3,477,728, issued Nov. 11, 1969, to Lindsay et al, for a "Cylinder-Type Talking Mechanism", the governor used therein being similar to that used in the above-discussed Lindsay U.S. Pat. No. 3,370,855.
A "Sound Reproducing Apparatus" is shown and described in U.S. Pat. No. 3,635,479, issued to Osante on Jan. 18, 1972, such patent disclosing a pair of arcuate weights pivotally coupled to a rotatable member with the outer periphery of the weights configured for frictionally engaging the inner surface of a drum like housing to regulate the speed of the sound reproduction medium.
Another "Sound Reproducing Device" is shown and described in U.S. Pat. No. 3,904,210, issued to Licitis, on Sept. 9, 1975, the device using a governor having a metallic disc rotating within an electromagnetic field created by a pair of oppositely positioned magnets on a U-shaped bracket, the disc rotating between the magnets to thus cut the lines of force created thereby.
Magnets, electromagnets and the general concept of the use of the force generated by such devices have been commonly used for devices other than governors. One such use, in measuring instruments, is shown in U.S. Pat. No. 2,263,264, issued Nov. 18, 1941 to Duwe, for a "Magnetic System for Measuring Devices", the patent disclosing a speedometer which employs the principle of the generation of eddy currents within a non-magnetic conducting member when interrupting the lines of force of a magnetic field.
U.S. Pat. No. 2,303,638, issued Dec. 1, 1942, entitled "Magnetic Transmission or Clutch", uses magnetic coupling between a driven and driving member in a clutch or transmission assembly.
U.S. Pat. No. 3,656,815, entitled "Vehicle Antiskid-Brake-System with Accelerometer", issued to Talebi, et al, on Apr. 18, 1972, and uses a solid cylindrical ferromagnetic rotor rotationally coupled to a vehicle wheel, the rotor being coated with a conductive nonferromagnetic material, with magnets generating an eddy current field in this coating, with pickup coils sensing the field to provide a differentiating signal which is a function of the angular acceleration of the rotor.
It is an object of the present invention to provide a new and improved sound reproducing mechanism for use in toys and the like.
It is another object of the present invention to provide a new and improved sound reproducing mechanism with magnetic governor means.
It is a further object of the present invention to provide a new and improved sound reproducing mechanism with a low cost magnetic governor.